//! \file PathSearch.h
//! \brief Defines the <code>fullsail_ai::algorithms::PathSearch</code> class interface.
//! \author Cromwell D. Enage, 2009; Jeremiah Blanchard, 2012
#ifndef _FULLSAIL_AI_PATH_PLANNER_PATH_SEARCH_H_
#define _FULLSAIL_AI_PATH_PLANNER_PATH_SEARCH_H_

#include "../TileSystem/Tile.h"
#include "../TileSystem/TileMap.h"
#include "../platform.h"
#include "../PriorityQueue.h"
#include <vector>
#include <deque>
#include <map>

#define NUM_OPERATORS	6

//#define _DEBUG_
//#define _DRAWING_

namespace fullsail_ai { namespace algorithms {

	struct Node
	{
		Node const* parent;
		Tile* state;
		float givenCost;
		float hCost;
		float finalCost;

		Node();
		Node(Node const* parent, Tile* _tile, float _givenCost, float _hCost, float _finalCost = 0.0f) : parent(parent), 
											state(_tile), givenCost(_givenCost), hCost(_hCost), finalCost(_finalCost) {}
	};

	class PathSearch
	{
	private:
		// Tree structures
		PriorityQueue<Node*> nodeList;			// open list
		std::map<Tile*, Node*> createdMap;		// duplicate tracker
		std::vector<Tile const*> solutionVec;	// final solution

		// Other
		TileMap* tileMap;
		Tile* startTile;
		Tile* goalTile;
		bool searchDone;
		Tile* adjTiles[NUM_OPERATORS];

		void GetAdjacentTiles(Tile const* _currTile);
		float Distance(Tile* _currTile, Tile* _goalTile);
		void DrawDebug(Node const* _currNode);

	public:
		//! \brief Default constructor.
		DLLEXPORT PathSearch();

		//! \brief Destructor.
		DLLEXPORT ~PathSearch();

		//! \brief Sets the tile map.
		//!
		//! Invoked when the user opens a tile map file.
		//!
		//! \param   _tileMap  the data structure that this algorithm will use
		//!                    to access each tile's location and weight data.
		DLLEXPORT void initialize(TileMap* _tileMap);

		//! \brief Enters and performs the first part of the algorithm.
		//!
		//! Invoked when the user presses one of the play buttons.
		//!
		//! \param   startRow         the row where the start tile is located.
		//! \param   startColumn      the column where the start tile is located.
		//! \param   goalRow          the row where the goal tile is located.
		//! \param   goalColumn       the column where the goal tile is located.
		DLLEXPORT void enter(int startRow, int startColumn, int goalRow, int goalColumn);

		//! \brief Returns <code>true</code> if and only if no nodes are left open.
		//!
		//! \return  <code>true</code> if no nodes are left open, <code>false</code> otherwise.
		DLLEXPORT bool isDone() const;

		//! \brief Performs the main part of the algorithm until the specified time has elapsed or
		//! no nodes are left open.
		DLLEXPORT void update(long timeslice);

		//! \brief Returns an unmodifiable view of the solution path found by this algorithm.
		DLLEXPORT std::vector<Tile const*> const getSolution() const;

		//! \brief Resets the algorithm.
		DLLEXPORT void exit();

		//! \brief Uninitializes the algorithm before the tile map is unloaded.
		DLLEXPORT void shutdown();
	};
}}  // namespace fullsail_ai::algorithms

#endif  // _FULLSAIL_AI_PATH_PLANNER_PATH_SEARCH_H_

